Device for controlling a plurality of electrical consumers

ABSTRACT

A device for controlling a plurality of electrical consumers to which a constant control current is applied at control nodes. A transformer unit to which a regulated and/or constant current having a predetermined frequency is applied at the input end comprises at least one first and a second winding at the output end which have a common tap, a first circuit branch forming a first control node for a first electrical consumer is associated with the first winding, and a second circuit branch forming a second control node for a second electrical consumer is associated with the second winding. Furthermore, the first and the second circuit branch each have a magnetically interacting pair of reactors which are wound in opposite directions relative to each other, and a first reactor of said pair is connected to the first control node via rectifying means, while a second reactor of the same pair is connected to the second control node via rectifying means. The reactors that are connected to one of the control nodes are wound in opposite directions. The pairs of reactors are magnetically coupled, in particular having a common reactor core.

BACKGROUND OF THE INVENTION

The present invention relates to a device for controlling a plurality ofelectrical consumers according to the preamble of the main claim.Electrical consumers may have LEDs in the form of strands in particular.On the other hand, the invention includes and claims the act ofproviding these electrical consumers in the form of electrical consumerswhich do not have semiconductor-based lamps, in particular no LEDs, andinstead are implemented as batteries (in which case the presentinvention is then embodied to control a plurality of such batteries as acharging device) and additionally or alternatively, the electricalconsumers have electric motors, or again alternatively, they may have aplurality of galvanic devices to which a constant electrical current issupplied.

With regard to the state of the art, reference should first be made tothe LED technology.

In particular for the purpose of manufacturing intensely bright lights,(high-performance) LEDs in strand form are combined as a seriesconnection, to then be able to deliver the cumulative light intensity(on a suitable carrier). FIG. 2 illustrates such an arrangement, inwhich a first control node CH1 and a second control node CH2 eachrepresent the switching point for a series connection of a plurality ofLEDs (10 per strand here).

The need for achieving a uniform light output of each LED leads to thefact that they are arranged as a series connection in the mannerdescribed here; a typical voltage drop of approximately 3.2V with awhite LED then results in voltages of approximately 32V being appliedper strand in the arrangement illustrated in FIG. 2. From the goal ofnot exceeding safety limits for low voltages, this leads to the resultthat multiple strands are carried in parallel, for example, with twostrands in the manner illustrated in FIG. 2, when orders of magnitude of15 to 20 LEDs are exceeded.

However, component tolerances and other manufacturing-related deviationsresult in the fact that, in the absence of separate measures, parallelcircuits of multiple strands will develop voltage differences, theresult being an uneven current distribution among the individualstrands. This leads to an irregular brightness of the respective LEDs inan advantageous manner and leads to disadvantages in terms of thelifetime of the lamps.

Accordingly, to achieve a uniform luminous efficiency ofparallel-connected strands, each having a plurality of LED lamps, it iscustomary in the state of the art to connect a current regulatorupstream from each strand to adjust and/or regulate the current (I1 instrand 1, I2 in strand 2 in FIG. 2) flowing in the strand at the samelevel.

However, this is complicated because a separate current regulating unitis required for each strand, so that there is a demand for a simplifiedcurrent regulation for a plurality of parallel strands of LED lampsprovided in the form of a series connection, in particular in the fieldof large-scale manufacturing technology and/or consumer applications.Furthermore, this basic demand exists not only for the LED lamps, whichare used only for the context of this problem but instead there is alsosuch a demand for any consumers, typically those such as batteries (tobe charged) which receive a constant (regulated) current, electricmotors (in particular stepping motors) or galvanic systems. All theseconsumers as well as additional electrical consumers which are typicallyoperated at a constant current are considered to be “electricalconsumers” in the remaining text in the sense of this invention, whereina preferred implementation form of the invention excludessemiconductor-based lamps, in particular LEDs, from the invention.

The object of the present invention is therefore to simplify a genericdevice for controlling a plurality of electrical consumers, inparticular to reduce the structural complexity and/or hardwarecomplexity, while at the same time providing a circuit which makes itpossible to apply a current to the plurality of electrical consumers andto do so in an energy-efficient manner with a minimal power loss.

SUMMARY OF THE INVENTION

This object is achieved by a device for controlling a plurality ofelectrical consumers to which a constant control current is applied atcontrol nodes. A transformer unit to which a regulated and/or constantcurrent having a predetermined frequency is applied at the input endcomprises at least one first and a second winding at the output endwhich have a common tap, a first circuit branch forming a first controlnode for a first electrical consumer is associated with the firstwinding, and a second circuit branch forming a second control node for asecond electrical consumer is associated with the second winding.Furthermore, the first and the second circuit branch each have amagnetically interacting pair of reactors which are wound in oppositedirections relative to each other, and a first reactor of said pair isconnected to the first control node via rectifying means, while a secondreactor of the same pair is connected to the second control node viarectifying means. The reactors that are connected to one of the controlnodes are wound in opposite directions. The pairs of reactors aremagnetically coupled, in particular having a common reactor core.

It is advantageously provided according to the invention that the totalcurrent which is kept constant and/or regulated and applied at theprimary side is divided between two single individual currents at thesecondary side of a main transformer (transformer unit and/or upstreamdevice), it is preferable to provide for the division to be into equalindividual currents on the secondary side through suitable identicaldesign of the number of windings (winding numbers) of the windings onthe secondary side, such that by adjusting the transmission ratio, adifferent adjustment may also be made.

According to the invention, a pair of throttles in the manner of acurrent transformer is now provided in each of the circuit branches onthe secondary side, said pair consisting of oppositely wound throttles,which cooperate magnetically with one another (these throttles beingprovided on a common throttle core, for example). Rectifier means, e.g.,a diode for half-wave rectification, are then connected downstream fromthese throttle coils in the direction of the first and/or second controlnodes for the electrical consumers (FIG. 2), such that a first throttleof the throttle pair is connected in this way to the first control nodeand the (oppositely wound) second throttle coil of the pair is connectedto the second control node via the rectifier means. Accordingly, for thesecond circuit branch, the first throttle is connected to the firstcontrol node and the second throttle is connected to the second controlnode, each being rectified, such that the throttles are wired, so thatthrottles connected to one control node (i.e., one of each of the twopairs) are also oppositely wound.

Since the throttle pairs are also magnetically linked to one another,for example, (all of them) also being provided on the same throttlecore, it is advantageously achieved through such a device that eachthrottle pair in the manner of a current converter divides the currentfor the half-waves (such that in the preferred case of the same numberof windings, this ratio amounts to 1:1, whereas with different numbersof windings, the currents are inversely proportional to the transmissionratio in the throttle pair).

The antipole design (i.e., the opposite windings of the individualthrottles of a throttle pair on a common core) advantageously results inthe magnetic fluxes of the windings canceling one another out via thesignal characteristic. With regard to the intended current regulationfor a plurality of electrical consumers, for example, for controllingthe control nodes CH1 and/or CH2 (FIG. 2) and a voltage difference inthese strands due to components and/or tolerance, this advantageouslyleads to the result that the currents introduced by the first and/orsecond circuit branch into the control nodes still remain constant, justas before, while a voltage difference between CH1 and CH2 magnetizes thecore. However, since a suitably repolarized voltage difference occurswith a following half-wave, there is a demagnetization and/orremagnetization that occurs for the core.

Accordingly, for implementation of the invention, a respective throttlepair is to be designed and embodied with a respective absolute number ofwindings per coil according to a maximally occurring voltage differencebetween the strands and/or a desired maximal deflection of the core(taking into account its geometry).

In the further embodiment according to the invention, this even makes itpossible for a control node (and/or a respective electrical consumer) tobe short-circuitable by switching a short-circuit to ground (the currentthereby increases only by its high-frequency component, which wouldotherwise be short-circuited by a respective filter capacitor. However,in such a case, the voltage supplied by the main transformer would beonly half as great, so then only half the power would be consumed, basedon the output current).

It is also advantageous that the principle according to the invention isnot limited to providing a throttle pair for each circuit branch and/orfor each control node. Instead the output signal of a throttle pair canbe used according to the refinement and in the manner of a cascade tocontrol two additional throttle pairs in a suitable manner in turn sothat in this way the number of control nodes to be controlled (and alsothe electrical consumers provided at these control nodes) is increasedaccordingly. As a result, n electrical consumers may each receive aconstant current (and/or an ideally equalized) control current with n−1divider transformers (wherein such a divider transformer provides twothrottle pairs on one common core).

As a variant to this cascaded embodiment of the invention, it isprovided according to the invention (and has also been claimedindependently) to provide an embodiment in the manner of a pairedcoupling of neighboring channels for the respective control nodes, inwhich a first throttle of a first throttle arrangement is connecteddownstream from the first winding of the transformer unit on thesecondary side, this embodiment being connected to the first of thecontrol nodes via rectifying means, and a third throttle is connecteddownstream from the first throttle arrangement, which is connected tothe second of the control nodes via rectifier means. However, a secondthrottle of the first throttle arrangement is connected downstream fromthe second winding of the transformer unit on the secondary side and isconnected to the first of the control nodes via rectifier means, and afourth throttle is connected downstream from the first throttlearrangement and is connected to the second of the control nodes viarectifier means. According to the invention, an oppositely woundthrottle of a second throttle arrangement is connected upstream from thesecond and fourth throttles, such that this second throttle arrangementis connected to the two individual throttles between the first and/orsecond winding on the secondary side and the first throttle arrangement.The throttles of the second throttle arrangement are advantageouslywound in opposite directions from one another according to theinvention, likewise with the throttles of the first throttle arrangementwhich are connected to a respective one of the control nodes being woundin opposite directions from one another (i.e., for example, the firstthrottle and the second throttle of the first throttle arrangement,which are connected to the first control node). In addition, thethrottles of the respective throttle arrangements are alsoadvantageously interconnected magnetically according to the invention,especially advantageously being provided on a common throttle core.

In an inventive refinement of this variant of the invention, it is alsopossible to galvanically separate the respective control nodes (and/orthe respective circuit branches, i.e., throttles of the first and/orsecond throttle arrangements connected upstream from the control node).To this end, the transformer unit has a plurality of first and secondwindings on the secondary side, each being assigned to these branchesand separated from one another and/or insulated from one another.

According to an especially favorable variant of the invention, for whichprotection is claimed independently, only one winding is present on thesecondary side of the main transformer. Here again, providing a throttlepair (magnetically linked together) in the manner described here alsoleads to the desired result, but with such a simplified (andasymmetrical) topology, one must ensure that the magnetization of thecore occurring due to voltage differences is suitably demagnetized.Within the scope of this aspect of the invention, it is thereforeadvantageous to provide a demagnetizing unit with an auxiliary winding,which leads to a demagnetization potential, more preferably with thehelp of a (bridge) rectifier or this auxiliary winding with a center tapand two-way rectification, which thus causes the demagnetization of thecore; in the exemplary embodiment described above, this was accomplishedthrough the alternating half-waves in a normal-mode configuration and/ora center tap of the secondary winding.

Within the scope of the invention, it is preferable to implement theplurality of electrical consumers according to the invention not asLEDs, but instead to provide as electrical consumers only thoseconsumers which do not have any semiconductor-based lamps, in particularno LEDs. It is especially preferred according to the invention toprovide a plurality of (rechargeable) batteries as the plurality ofelectrical consumers, such that in this case the device according to theinvention may be implemented as a charger. Alternatively, it is providedwithin the scope of preferred implementations of the invention toprovide the plurality of electrical consumers in the form of a pluralityof (electric) motors, in particular as stepping motors, which receive aconstant current in the manner according to the invention. Furthermore,according to the invention, it is provided within the scope of preferredfurther embodiments of the invention that the plurality of electricalconsumers is to be embodied as devices for galvanics and/or galvanictreatment of workpieces which receive the constant current in the manneraccording to the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

Additional advantages, features and details of the invention are derivedfrom the following description of preferred exemplary embodiments aswell as on the basis of the drawings, which show:

FIG. 1 a schematic wiring diagram of the device for controlling aplurality of electrical consumers according to a first exemplaryembodiment of the invention;

FIG. 2 a schematic line diagram to illustrate two electrical consumersprovided parallel to one another;

FIG. 3 a modification of the exemplary embodiment of FIG. 1 by a shortcircuit and/or dimmer unit assigned to one of the two control nodes;

FIG. 4 a further embodiment of the exemplary embodiment of FIG. 1 in acascaded two-stage system of throttle pairs for controlling fourelectrical consumers;

FIG. 5 a variant of the invention with only one winding of the maintransformer on the secondary side such that the throttle pair assignedto the first and/or second control node(s) additionally cooperates withan auxiliary winding for demagnetization;

FIG. 6 an embodiment of the invention as a variant of FIG. 4, in which,instead of a cascaded system, a paired coupling of neighboring channelsis performed and

FIG. 7 a further embodiment of the exemplary embodiment of FIG. 6 inwhich separate first and/or second windings of the (main) transformer onthe secondary side are provided for each respective channel of a controlnode in order to separate the circuit branches thereby formed from oneanother.

DETAILED DESCRIPTION

FIG. 1 illustrates the essential components of the first exemplaryembodiment of the invention. A pair of secondary windings 12, 14, whichare joined to one another via a center tap 13 and form circuit branches16 and/or 17, is formed on the secondary side of a main transformer 10.A throttle pair 20 consisting of a pair of oppositely wound throttles24, 26 on a common core are provided in the upper circuit branch 16 (thedots in the wiring diagram indicate the direction of winding in a mannerwhich is otherwise known). Similarly, a throttle pair 22 consisting ofthe individual oppositely wound throttles 28, 30 is provided for thesecond circuit branch 18. In the present exemplary embodiment withidentical secondary windings 12, 14 with regard to the number ofwindings as well as with the same number of windings of the throttles 24to 30, there is thus a symmetrical arrangement to this extent. All ofthe individual throttles 24, 26, 28, 30 are formed by means of a commonthrottle core and cooperate magnetically to this extent.

As further illustrated by the diagram in FIG. 1, one output (pole) ofthe throttle 24 is connected to the first control node CH1 via arectifier diode 32 (FIG. 2), such that this control node is connected toground (GND) across a filter capacitor 40. The second throttle 26 of thefirst throttle pair 20 is connected to the control node CH2 via acorresponding rectifier diode 36; this control node also has ahigh-frequency connection to ground across a filter capacitor 42.

Similarly and symmetrically with the first throttle pair 20, theindividual throttles 28, 30 of the second throttle pair 22 lead overrectifier diodes (rectifier means) 34, 38 to the control nodes CH1and/or CH2. It can be seen from the diagram in FIG. 1 that theindividual throttles (e.g., 24, 28 for CH1) leading to a control nodeare also wound oppositely from one another (likewise the individualthrottles 26, 30 with regard to CH2).

During operation, the device shown here is supplied with a regulatedand/or constant primary current on the primary side (in the manner of aconventional upstream device), such that this primary current then flowsalternately in the secondary windings 12, 14 and/or in the branches 16and 18 thus formed, depending on which half-wave is prevailing. Therespective throttle pairs 20 and/or 22 then act in the manner of acurrent transformer, such that the current in branch 16 is divided amongthe throttles 24, 26 (at an assumed winding ratio of 1:1). The magneticfluxes of the windings cancel one another due to the opposing polarity.A similar situation applies to throttle pair 22 in branch 18. It isadvantageously found that although a voltage difference from CH1 to CH2(each relative on ground) produces magnetization of the core, this iscompensated and/or canceled with a subsequent repolarized half-wave.

In the exemplary embodiment shown here of a frequency of the appliedcurrent in the range between approximately 100 and 200 kHz (a rangebetween 30 and 500 kHz is conceivable) and a maximum voltage at CH1and/or CH2 in the range between approximately 40 and 50V (usuallycorresponding to 10 to 15 LEDs per strand), the throttles 24 to 30 havetypical winding numbers from a few up to hundreds. Filter capacitors 40and/or 42 are within the range of 1 μF to 10 mF.

In a refinement of the exemplary embodiment of FIG. 1, it is possible tomodify the number of windings of the throttles, such that the number ofwindings must be the same for the respective half-waves to one controlnode, i.e., the number of windings of the throttle 24=the number ofwindings of the throttle 28, and the number of windings of the throttle26=the number of windings of the throttle 30. The ratios of thesenumbers of windings to one another then defines the ratio of thecurrents in the control nodes, i.e., winding ratio of throttle 24 towinding ratio of throttle 26=I2 (in CH2):I1 (in CH1).

FIG. 3 illustrates a preferred and advantageous modification of theexemplary embodiment of FIG. 1. With otherwise the same components, ashort-circuit unit is connected downstream from the throttles 26 and/or28 for the node CH2, said short-circuit unit consisting essentially ofan FET 50 as a switching element controlled at its gate 52, such thatdecoupling diodes 54, 56 are assigned to the throttle outputs.

Then a clocked and/or periodic and/or modulated control of the gateterminal 52, for example, permits dimming of the LED strand connected atCH2, in that a short-circuit to ground takes place in accordance withthe “on” time of the FET 50, and this portion of the current, which istapped off to ground, is no longer available for the CH2.

The transistor 50 also permits voltage regulation, e.g., by the factthat the transistor 50 influences the charging and/or dischargingperformance of the capacitor 42 (for example, between two controlvalues) through its switching behavior. If the modulation and/or anon:off pulse duty factor at the switching input 52 of the transistor 50is/are altered, the strand current (12 to CH2 here) can be adjustedsuitably between 0 and 100% preselected rated value. The current in theother strand (CH2) remains unchanged in this configuration as long asthe current supplied by the main transformer 10 remains constant.

If in a variation of the principle of FIG. 3, the filter capacitor isshifted to the primary side (not shown) of the main transformer, then asimplification in the technical circuitry, namely removal of thecapacitors, is possible on the secondary side such that theshort-circuit switch (transistor 50) can then be connected directly tothe output even without the decoupling diodes shown (54, 56).

FIG. 4 illustrates another modification in the form of a cascade.

Additional throttle pairs 60, 62, 64, 66 are provided here, such thatthe throttle pairs 20, 22 sit on a common core (in continuation of theexemplary embodiment of FIG. 1 in a cascaded form), ditto for thethrottle pairs 60, 62 having a common core and throttle pairs 64, 66having a common core. The individual throttles of the throttle pairs 60to 66 are again wound oppositely, and in the exemplary embodiment ofFIG. 4, a separate short circuit according to FIG. 3 is assigned to eachstrand (thus control nodes CH1 to CH4), so there is the greatestpossible flexibility in wiring and/or modulation of the gate terminals70 to 76.

If the throttle pairs 20, 22 as well as 60, 62 and 64, 66 are eachinterpreted as divider transformers, then a current regulation for atotal of four strands and/or control nodes can be implemented with atotal number of three divider transformers, or an implementation of nstrands by n−1 divider transformers in generalized form.

The principle shown here is possible with any normal-mode main convertercircuits including half bridge, full bridge, resonant converter, Mcircuit, etc.

For example, if the respective diodes are reversed in polarity as anexample of an output, then a negative output voltage is applied at thecorresponding control node and/or a negative output current flows. Thiscurrent corresponds in amount to the positive current and can beadjusted as described above by stipulating corresponding transmissionratios. For example, if the polarity of the diodes (70, 72) is reversedfor the control node CH4 (FIG. 4), then CH4 is negative with regard tocurrent and voltage accordingly. The polarity of the decoupling diodes(74, 76) should also be reversed for the switching transistor (50) inthis branch, in which case this short-circuit switch would then beimplemented as a P channel transistor.

A current flows here through the upper winding (64), then the samecurrent also flows through the lower winding of the pair (66), but inthe opposite direction, for example, during the positive half-wave.Since these two windings have the same direction of winding but thecurrents are now opposite from one another, the principle describedabove is applicable. In the preceding divider stage (windings 20 and/or22), the magnetic fluxes are added up and the windings 20 (lowerwinding) and 22 (lower winding), the direction of winding and thecurrents are in opposition and advantageously create the balance withthe current in the winding 20 (above) according to the invention.

It follows that the absolute current division is maintained in themanner provided according to the invention again in this case of anoutput with a reversed polarity.

FIG. 5 illustrates another modification of the basic principle of FIG.1, but in a further simplification, this turns away from the normal-modeprinciple of FIG. 1 (in which both half-waves of the main transformersignal are advantageously utilized and in particular can also be usedfor demagnetization). In a further simplified exemplary embodiment ofFIG. 5, the secondary side has only one winding 80, downstream fromwhich a throttle pair (oppositely wound) 82, 84 on a common core isconnected and in turn leads over rectifier diodes 32, 34 to the controlnodes CH1, CH2. Again, filter capacitors 40, 42 ensure a high-frequencyground connection.

However, since there is a magnetization of the throttle core (whichwould not be demagnetized in the half-wave of the opposite polarity, aswith the normal-mode circuit described above) due to the single-cycleimplementation of FIG. 5 and the potentially irregular voltages on CH1and/or CH2, a demagnetization is implemented in the form of an auxiliarywinding 86 connected to a bridge rectifier 88 and a filter capacitor 90to an auxiliary potential U_(hilf).

The demagnetizing winding 86 may also be fed back to the primary side(with appropriate insulation).

The principle illustrated in FIG. 5 functions with single-cycle fluxconverters as well as flyback converters. With all types of fluxconverters (including normal-mode), a throttle with a demagnetizingdiode also sits between the rectifier and the filter capacitor. Theembodiment according to FIG. 5 can also be refined by means of theregulation and/or dimming of FIG. 3.

FIGS. 6 and 7 show another implementation of the invention whichrepresents a variant through coupling of neighboring channels incomparison with the cascaded design of the invention according to FIG.4.

In concrete terms the transformer unit 10 again has two windings 12and/or 14 on the secondary side which have a shared tap to ground GND.

As also shown from the diagram in FIG. 6, each of the windings 12, 14leads to one of the four control nodes CH1 to CH4, which in turn, as inthe manner described above, offer a current division and/or currentlimitation for electrical consumers (not shown), which can be connectedthere. To be more specific, with regard to the control nodes CH1, athrottle pair 70 (referred to as TR3-A and TR3-B in the wiring diagram)is connected upstream as a rectifier means via diodes D1, this throttlepair sitting on a common core and wound oppositely from one another. Twoother individual throttles of a throttle pair 72 (TR3-C and TR3-D in thewiring diagram) are also part of the same throttle arrangement, sit onthe same core and to this extent form part of a branch directed at thesecond control node CH2 (again via rectifiers D2). A throttle pair of asecond throttle arrangement is connected upstream from the throttle pair72, a first throttle TR2-A leading to the first winding 12 on thesecondary side and a second throttle TR2-B of the pair 80 leading to thesecond winding 14.

With regard to a further throttle arrangement consisting of throttlepairs 74 (for the third control node CH3) and 76 (for the fourth controlnode CH4) the exemplary embodiment of FIG. 6 is designed symmetrically(based on the first throttle arrangement with the pairs 70, 72). Againthe throttle pairs 74, 76 sit on a common core. Throttles of a throttlepair 82 are connected upstream from the throttle pair 74 such that thethrottle pair 82 together with the throttle pair 80 forms a separatethrottle arrangement (again on a common core) as described above.

The respective throttle arrangements 70, 72 and 74, 76 as well as 80, 82have a transmission ratio of 1:1. As a result a current I1 to the firstcontrol node CH1 is equal to the current I2 to the second control nodeCH2. The additional throttle arrangements are designed accordingly, suchthat the throttle arrangement (transformer) 80, 82 ensures that I2=I3,and the throttle arrangement 74, 76 (transformer) ensures that I3=I4accordingly.

As a result, it holds that I1=I2=I3=I4, so that each output current inone of the control nodes CHi (i=1 to 4) has a quarter of the valuepredetermined by the main transformer 10 (and/or its control on theprimary side).

The wiring diagram in FIG. 6 shows that the transformer with thethrottle pairs 80, 82 acts in principle like the throttle arrangementwith the throttle pairs 20, 22 in the exemplary embodiment of FIG. 4.Fundamentally, windings that operate with the same phase angle of theinput signal (i.e., the upper or the lower individual throttle of thepairs 80, 82 in FIG. 6) are formed with opposite directions of winding.This is also true of individual windings leading to a shared controlnode, as is the case for the individual throttles of the pair 70, 72,etc.

The circuit principle of the exemplary embodiment of FIG. 6 can also beexpanded to any desired number of other channels. Like the principledescribed above, n−1 divider transformers (i.e., throttle arrangementsin the sense described above) are necessary for n output channels, as inthe exemplary embodiment of FIG. 4. It is likewise possible for theprinciple of the invention of FIG. 6 to include individual dimming bychannels via additional decoupling diodes as well as a short-circuitswitch (reference numerals 50, 52 in FIG. 4).

If an output signal (control node) has one current value that isdifferent from the others, then the transmission ratio of the throttlearrangements connected to the respective control node is to be adjusted,wherein the aforementioned rules are applicable. For example, if adifferent current value flows in the node CH2 in the circuit of FIG. 6than in the nodes CH1, CH3, CH4, then the transmission ratio of thethrottle pair 80:82 must be the same as the transmission ratio of thethrottle pair 72:70 in order to set a different current I2.

Within the context of the preferred refinements of the invention, it isalso possible to combine the principles of the exemplary embodiment ofFIG. 4 (cascading) and/or of FIG. 6 (paired wiring) with one another.For example, it is possible that one output (control node) of thecircuit of FIG. 6 is divided with another distributor transformer(throttle arrangement) into two channels, as shown in FIG. 1. Likewise,one output (control node) of the circuit from FIG. 4 may supply thearrangement according to FIG. 6, for example, and then this output maybe divided among four channels.

FIG. 7 shows a variant of the exemplary embodiment of FIG. 6, whereinthe same reference numerals denote corresponding matching circuitcomponents. In contrast with FIG. 6, the current divider circuit on thesecondary side is divided into a plurality of circuit branches separated(galvanically) from one another, channel by channel, such that eachcircuit branch is assigned to one of the control nodes for the consumersto be allocated and each has a (separate) winding pair of the maintransformer on the secondary side, referred to in the example of FIG. 7as 12 i′ and/or 14 i′ (where i=1 to 4 according to the respectivecircuit branch).

Due to this division of the main transformer 10 into a plurality ofmutually insulated secondary windings, there is a magnetic decoupling ofthe four channels shown. A similar phase angle is to be ensured for eachchannel according to the allocation and design of the windings 12, 14 ofFIG. 6 on the secondary side.

1. A device for controlling a plurality of electrical consumers, whichreceive a constant control current (I1, I2) at the respective controlnodes (CH1, CH2), comprising: a transformer unit (10) which receives aregulated and/or constant current at a predetermined frequency on theprimary side has at least one first winding (12) and a second winding(14) on the secondary side having a shared tap (13), a first circuitbranch (16) forming a first control node (CH1) for a first electricalconsumer is assigned to the first winding, and a second circuit branch(18) forming a second control node (CH2) for a second electricalconsumer is assigned to the second winding, the first and the secondcircuit branches each have a mutually oppositely wound and magneticallycooperating throttle pair (20, 22), wherein a first throttle (24; 28) ofthe throttle pair is connected to the first control node via rectifiers(32; 34), and a second throttle (26; 30) of the same throttle pair isconnected to the second control node via rectifiers (36; 38), withthrottles connected to one of the control nodes wound oppositely fromone another, and the throttle pairs being magnetically coupled, inparticular having a common throttle core.
 2. The device according toclaim 1, wherein the transformer unit has two windings (12, 14) on thesecondary side with a center tap (13) to form the first and secondcircuit branches for a positive and negative half-wave of the signaltransmitted.
 3. The device according to claim 1, wherein the throttlesassigned to one control node have the same number of windings.
 4. Thedevice according to claim 1, wherein the throttles of a throttle pairhave the same number of windings.
 5. The device according to claim 1,wherein according to the predetermined frequency, the control nodes areconnected to ground potential (GND) via capacitance means (40, 42). 6.The device according to claim 5, wherein the capacitance means areconnected downstream from the rectifiers.
 7. The device according to anyclaim 1, wherein a throttle pair (60; 62; 63; 66) having a first and asecond throttle is connected downstream from each throttle of a throttlepair (20; 22) in the manner of a cascade.
 8. The device according to anyclaim 1, wherein short-circuit means (50, 52, 54, 56) which areconnected at the output end to the at least one throttle (26, 30)assigned to the circuit nodes (CH2), so that the throttle outputupstream from the rectifiers is connected to ground potential inresponse to a first control of the short-circuit means.
 9. The deviceaccording to claim 8, including PWM-modulated control of theshort-circuit means.
 10. The device for controlling a plurality ofelectrical consumers which receive a constant control current at therespective control nodes (CH1, CH2), comprising: a transformer unitreceiving a regulated and/or constant current of a predeterminedfrequency on the primary side and having a winding (80) without a tap onthe secondary side, a first circuit branch forming a first control node(CH1) for a first electrical consumer and a second circuit branchforming a second control node (CH2) for a second electrical consumerbeing assigned to the winding, the first and the second circuit brancheshaving a pair of oppositely wound and magnetically cooperating throttles(82, 84), wherein a first throttle (82) of the throttle pair is incontact with the first control node via rectifiers (32), and a secondthrottle (84) of the same throttle pair is applied to the second controlmode via rectifiers (34), and a demagnetizing unit having an auxiliarywinding (86), which cooperates magnetically with the throttle pair isassigned to the throttle pair.
 11. The device according to claim 10,wherein the auxiliary winding has a rectifier unit (88), in particular abridge rectifier unit connected to a demagnetizing potential (U_(hilf)).12. The device for controlling a plurality of electrical consumers whichreceive a constant control current at the respective control nodes (CH1,CH2, CH3, CH4), comprising: a transformer unit (10) receiving aregulated and/or constant current of a predetermined frequency has atleast one first winding (12) and one second winding (14) on thesecondary side having a shared pickup, a first throttle of a firstthrottle arrangement (70, 72), which is connected to a first one (CH1)of the control nodes via rectifiers (D1) is connected downstream fromthe first winding, and a third throttle of the first throttlearrangement is also connected downstream and is connected to a secondone of the control nodes (CH2) via rectifiers (D2), a second throttle ofthe first throttle arrangement, which is connected to the first one(CH1) of the control nodes via rectifiers (D1), is connected downstreamfrom the second winding, and a fourth throttle of the first throttlearrangement is connected downstream from the second winding and isconnected to the second one (CH2) of the control nodes via rectifiers(D2), one oppositely wound throttle of a second throttle arrangement(80, 82) is connected upstream from the second and fourth throttles,said throttle arrangement being provided between the first and/or secondwindings of the transformer unit on the secondary side, said throttlesof the first throttle arrangement being connected to the respectivecontrol nodes and being oppositely wound from one another, and thethrottles of the first throttle arrangement and the throttles of thesecond throttle arrangement are each coupled magnetically to oneanother, in particular having a common throttle core.
 13. The deviceaccording to claim 12, wherein a respective circuit branch is formed foreach of the control nodes having the throttles of the first throttlearrangement connected to the respective control nodes and having thefirst and second windings of the transformer unit on the secondary side,wherein for separating the circuit branches from one another, the firstwindings on the secondary side (12 i′) and the second windings (14 i′)on the secondary side of the transformer unit (10) are each separatedfrom one another and insulated.
 14. The device according to any claim 1,wherein the plurality of the electrical consumers has a plurality ofchargeable batteries and/or accumulators or a plurality of electricmotors or plurality of galvanic plants.
 15. The device according to anyclaim 1, wherein the plurality of the electrical consumers are free ofany semiconductor-based lamps and/or organic lamps.